Incorrect. The paragraph I quoted is 261(b). The paragraph you are talking about is 261(a)(7), part of 261(a). Note that 261(a)(7) never even uses the word "duress".
Furthermore, 261(b) says "this section". The "section" is 261, not 261(a)(7). Note also that 261(a)(7) calls itself "this paragraph", not "this section".
You are right, I'm misunderstanding the scoping rules for law. I was interpreting it as (261 ... (7 ... (b ...))) rather than (261 (a ... (7 ...) ) (b ...) ).
I guess the question hinges on what is intended by the word "retribution".
Furthermore, 261(b) says "this section". The "section" is 261, not 261(a)(7). Note also that 261(a)(7) calls itself "this paragraph", not "this section".
261.7 is a completely different section concerning the evidentiary value of birth control methods: http://codes.lp.findlaw.com/cacode/PEN/3/1/9/1/s261.7